content: /* ===========================================================
   * JFreeChart : a free chart library for the Java(tm) platform
   * ===========================================================
   *
   * (C) Copyright 2000-2012, by Object Refinery Limited and Contributors.
   *
   * Project Info:  http://www.jfree.org/jfreechart/index.html
   *
   * This library is free software; you can redistribute it and/or modify it
   * under the terms of the GNU Lesser General Public License as published by
   * the Free Software Foundation; either version 2.1 of the License, or
   * (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
   * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
   * License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
   * USA.
   *
   * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
   * Other names may be trademarks of their respective owners.]
   *
   * ---------------------------
   * CategoryCrosshairState.java
   * ---------------------------
   * (C) Copyright 2008, by Object Refinery Limited and Contributors.
   *
   * Original Author:  David Gilbert (for Object Refinery Limited);
   * Contributor(s):   -;
   *
   * Changes
   * -------
   * 26-Jun-2008 : Version 1 (DG);
   *
   */
  
  package org.jfree.chart.plot;
  
  import java.awt.geom.Point2D;
  
  import org.jfree.chart.renderer.category.CategoryItemRenderer;
  
  /**
   * Represents state information for the crosshairs in a {@link CategoryPlot}.
   * An instance of this class is created at the start of the rendering process,
   * and updated as each data item is rendered.  At the end of the rendering
   * process, this class holds the row key, column key and value for the
   * crosshair location.
   *
   * @since 1.0.11
   */
  public class CategoryCrosshairState extends CrosshairState {
  
      /**
       * The row key for the crosshair point.
       */
      private Comparable rowKey;
  
      /**
       * The column key for the crosshair point.
       */
      private Comparable columnKey;
  
      /**
       * Creates a new instance.
       */
      public CategoryCrosshairState() {
          this.rowKey = null;
          this.columnKey = null;
      }
  
      /**
       * Returns the row key.
       *
       * @return The row key.
       */
      public Comparable getRowKey() {
          return this.rowKey;
      }
  
      /**
       * Sets the row key.
       *
       * @param key  the row key.
       */
      public void setRowKey(Comparable key) {
          this.rowKey = key;
      }
  
      /**
       * Returns the column key.
       *
       * @return The column key.
       */
      public Comparable getColumnKey() {
          return this.columnKey;
      }
  
      /**
       * Sets the column key.
       *
       * @param key  the key.
       */
      public void setColumnKey(Comparable key) {
          this.columnKey = key;
      }
  
      /**
       * Evaluates a data point from a {@link CategoryItemRenderer} and if it is
       * the closest to the anchor point it becomes the new crosshair point.
       *
       * @param rowKey  the row key.
       * @param columnKey  the column key.
       * @param value  y coordinate (measured against the range axis).
       * @param datasetIndex  the dataset index for this point.
       * @param transX  x translated into Java2D space.
       * @param transY  y translated into Java2D space.
       * @param orientation  the plot orientation.
       */
      public void updateCrosshairPoint(Comparable rowKey, Comparable columnKey,
              double value, int datasetIndex, double transX, double transY,
              PlotOrientation orientation) {
  
          Point2D anchor = getAnchor();
          if (anchor != null) {
              double xx = anchor.getX();
              double yy = anchor.getY();
              if (orientation == PlotOrientation.HORIZONTAL) {
                  double temp = yy;
                  yy = xx;
                  xx = temp;
              }
              double d = (transX - xx) * (transX - xx)
                      + (transY - yy) * (transY - yy);
  
              if (d < getCrosshairDistance()) {
                  this.rowKey = rowKey;
                  this.columnKey = columnKey;
                  setCrosshairY(value);
                  setDatasetIndex(datasetIndex);
                  setCrosshairDistance(d);
              }
          }
  
      }
  
      /**
       * Updates only the crosshair row and column keys (this is for the case
       * where the range crosshair does NOT lock onto the nearest data value).
       *
       * @param rowKey  the row key.
       * @param columnKey  the column key.
       * @param datasetIndex  the dataset axis index.
       * @param transX  the translated x-value.
       * @param orientation  the plot orientation.
       */
      public void updateCrosshairX(Comparable rowKey, Comparable columnKey,
              int datasetIndex, double transX, PlotOrientation orientation) {
  
          Point2D anchor = getAnchor();
          if (anchor != null) {
              double anchorX = anchor.getX();
              if (orientation == PlotOrientation.HORIZONTAL) {
                  anchorX = anchor.getY();
              }
              double d = Math.abs(transX - anchorX);
              if (d < getCrosshairDistance()) {
                  this.rowKey = rowKey;
                  this.columnKey = columnKey;
                  setDatasetIndex(datasetIndex);
                  setCrosshairDistance(d);
              }
          }
  
      }
  
  }
  